Final answer:
A heat pump system is primarily sized for the heating load.
Step-by-step explanation:
The primary purpose of a heat pump system is to provide **heating**. A heat pump transfers thermal energy from a colder environment to a warmer environment, using work input. It can also be used for cooling purposes, but it is primarily sized for the **heating load**. Heat pumps are designed to extract heat from a cold environment and deliver it to a warmer space, making them highly efficient for heating purposes.